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Re: Which extra would keep me warmer?

Posted: Wed Sep 18, 2019 6:57 pm
by Lazarus
yes reading fail on my part I really dint recall seeing the second part
sorry and ta

Re: Which extra would keep me warmer?

Posted: Wed Sep 18, 2019 11:19 pm
by composite
Bearbonesnorm wrote: Wed Sep 18, 2019 5:14 pm
I tried this a couple of times after you and chew suggesting it but it never worked out for me. Whenever I tried it I woke up cold in the night, pulled my down jacket back on and slept through the rest of the night nice and warm.
You were unzipping it and putting it inside your sleeping bag Neil?
You mean laying it on top of the tarp wasn't what you meant?!??!! :-P :-P :grin:

Yeah, I had it on the inside of the sleeping bag unzipped. If my mrs is to be believed, juries out... then I wiggle around a lot when I sleep so maybe that affects it. It's why I always use still use my bivi bag even in a bothy to make sure my mat stays put under me.

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 10:13 am
by Mart
If really cold you could make a warm/hot water bottle to take into your sleeping bag
Sounds silly but it doesn't take a lot of heat to make it super toasty

I usually wrap the bottle (plastic) in a big sock

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 11:46 am
by Cheeky Monkey
An improvised HWB is a common recommendation in hammocking spheres. Some suggest sticking it in your armpit, groin or near a major blood vessel, theory being it warms the blood which then circulates.

Never tried it as never felt the need / been cold enough so couldn't say if it's effective or worth the effort.

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 11:52 am
by Borderer
These are pretty cosy. I only paid £11 for ours a couple of years ago, so the price now seems very steep. You might be able to find a better deal somewhere though. They weigh 334g each btw.

https://www.ebay.co.uk/itm/Lifeventure- ... SwH09ZLsoU

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 5:31 pm
by benconnolli
Fan of the hot water bottle when you get caught out colder than expected and also have a stove and spare fuel. If you expect zero in the nights then you will probably have other warmer clothes for on the bike so make use of them sleeping too

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 6:37 pm
by BigdummySteve
Chemical heat packs between socks and down booties plus in your groin has got me through-5 in a 0deg bag, nice hat always helps :-bd

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 7:00 pm
by composite
Mart wrote: Thu Sep 19, 2019 10:13 am If really cold you could make a warm/hot water bottle to take into your sleeping bag
Sounds silly but it doesn't take a lot of heat to make it super toasty

I usually wrap the bottle (plastic) in a big sock
I read about racers on the iditarod creating "human powered" hot water bottles to stay warm. :o

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 7:47 pm
by RIP
Was thinking the same idea meself. However if you created a hot water bottle from your own, er, resources wouldn't that just temporarily extract, er, fluid-borne heat from your body some but not all of which would subsequently be radiated back to a different part of your body? On balance you'd be losing heat. Newton's 1st Law or summat or other?

And I still reckon eating/drinking 'hot' stuff must have a marginal effect given the mass of a body relative to the mass of, say, a mug of ovaltine or a lump of choc. I'd be interested to see the associated energy transfer equations if someone has the appropriate knowledge :smile: .

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 8:01 pm
by ScotRoutes
RIP wrote: Thu Sep 19, 2019 7:47 pm Was thinking the same idea meself. However if you created a hot water bottle from your own, er, resources wouldn't that just temporarily extract, er, fluid-borne heat from your body some but not all of which would subsequently be radiated back to a different part of your body? On balance you'd be losing heat. Newton's 1st Law or summat or other?
But you'd not be losing as much heat as you would if you tried to heat up the mass of the planet.

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 10:06 pm
by Lazarus
Pretty hard to refute that
As you are expelling the heat the only question is are you going to use it to warm you or the planet?

I have yet to be that cold.

Re: Which extra would keep me warmer?

Posted: Thu Sep 19, 2019 11:17 pm
by RIP
Yes I'm not proposing transferring my heat
to the planet if I can help it. I'm guessing that preventing heat loss has far more effect than trying to add heat. Hence the importance of the temperature and conductivity/convectivity of whatever's directly in contact with, mainly, your skin and therefore where one should be concentrating one's efforts - stopping your heat crossing that barrier. A nice little layer of still air in a windproof high-loft sleeping bag would be my vote.

Assuming you're eating/drinking normally, your 63000g body's going to be at 37c. I reckon last-minute drinks, food, heatpads, bottles, getting in the bag/quilt 'pre-warmed' (whatever that means) etc will only make you 'feel' warmer (and for a short period) which isn't the same as 'being' core-warm via cells continuously burning the day's food. There's probably even an argument that a hot drink fools your body into (temporarily) feeling warm, and therefore stops its automatic responses to cold of constricting blood vessels to prevent heat loss and shivering to create heat - so you'd lose heat quicker than if you hadn't had that drink. You could generate heat to maintain the air gap temperature by thrashing muscles around in your bag continuously all night if that suits I suppose. If you start sweating as well that'll compound the problem (best not have that rehydrated chili last thing then? :smile: ).

I'd like to investigate the physics/physiology more closely 'cos keeping warm in a bivvy is obviously a pretty important part of our experience...

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 6:21 am
by Al
I remember reading something on a lightweight backpacking site years ago that suggested sleeping with a disposable dust mask over your face like you use for diy. The idea was you lose a lot of heat warming the air you breathe in, so could get away with a thinner bag.
Can’t say I’ve ever tried it though - sounds unpleasant! Could be a lightweight emergency heat boost without adding any significant weight if it did work and it didn’t bother you.

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 6:22 am
by middleagedmadness
On a less serious note I do find less ale and more whisky in winter is what helps me sleep ,no need to get up at 4am for the old man p1ss ,so stay toasty warm in my bag instead

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 7:43 am
by whitestone
Al wrote: Fri Sep 20, 2019 6:21 am I remember reading something on a lightweight backpacking site years ago that suggested sleeping with a disposable dust mask over your face like you use for diy. The idea was you lose a lot of heat warming the air you breathe in, so could get away with a thinner bag.
Can’t say I’ve ever tried it though - sounds unpleasant! Could be a lightweight emergency heat boost without adding any significant weight if it did work and it didn’t bother you.
It does work though I don't use a dust mask but a neoprene face mask (no Gimp jokes at the back please!) - they tend to be sold either as ski face masks or for motorcyclists. I've only ever worn them when active in very cold conditions, Alpine winter climbing, so don't know how claustrophobic they'd feel when sleeping.

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 8:50 am
by RIP
I like MaM's idea - voice of reason with simple quick solutions :wink: .

'air you breathe' - I was thinking about that last night. It's all very well covering/insulating your body but your lungs effectively have a totally uninsulated contact with Colin's whole planet. Lung surface area is about half a tennis court, and the blood vessels are only separated from the 'outside' by a layer a couple of cells thick. Obviously this air is being rapidly changed - warmth and CO2 going out and cold air coming in. Opinions I read vary the heat loss via respiration from 'relatively minor', through '25-30%' at rest, up to '50%'! Good luck trying to solve that issue without suffocating in the process or using some clever heat-exchanger contraption strapped to your face!

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 9:24 am
by Bearbonesnorm
I'm liking the idea of one of these. Even if it does nowt to keep you warm, it'll scare the f*ck out of dog walkers.

Image

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 9:29 am
by whitestone
Bearbonesnorm wrote: Fri Sep 20, 2019 9:24 am I'm liking the idea of one of these. Even if it does nowt to keep you warm, it'll scare the f*ck out of dog walkers.

Image
Err, wasn't you was it? - https://www.bbc.co.uk/news/uk-england-bristol-48982140

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 9:59 am
by labrat
I've had the Snugpak travel blanket and not overly impressed - its an odd shape/sixe - not quite thick enough to keep you warm, yet also not quite wide enough, and not quite square enough to wear as a wraparound around camp.... just doesn't work, and the insulation shifts around too.

I wish they made one that was the size of a woobie (US army poncho liner) but made of the same thickness as the original softie jacket.

Until then, Dutch army poncho liner for the win.

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 2:53 pm
by RIP
Good grief Stu, didn't know Hannibal Lecter was a 'boner....

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 3:29 pm
by PaulB2
Not sure if the scuba mask and rubber ring is a better look...

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 7:41 pm
by Charliecres
Image

“Best night’s sleep I’ve had in ages ...”

Re: Which extra would keep me warmer?

Posted: Fri Sep 20, 2019 9:56 pm
by composite
Bearbonesnorm wrote: Fri Sep 20, 2019 9:24 am I'm liking the idea of one of these. Even if it does nowt to keep you warm, it'll scare the f*ck out of dog walkers.

Image
Picture the scene.

Stu in the workshop wearing this of an evening. Dee comes out with a brew, rolls her eyes, goes back inside.

Re: Which extra would keep me warmer?

Posted: Sat Sep 21, 2019 9:54 am
by RIP
I would imagine the only scene worse than that would be Stu still wearing it at bedtime..

Re: Which extra would keep me warmer?

Posted: Sat Sep 21, 2019 10:11 am
by middleagedmadness
Please,please stop I have a vivid imagination and you lot are ingraining images I don't want in it